Isorhamnetin alleviates lipopolysaccharide-induced acute lung injury by inhibiting mTOR signaling pathway.

Aim: Acute Lung Injury (ALI) is an acute hypoxic respiratory insufficiency caused by various traumatic factors, manifested as progressive hypoxemia and respiratory distress, and lung imaging shows a heterogeneous osmotic outbreak. Isorhamnetin (ISO) is a flavonoid compound isolated and purified from medicinal plants, such as Hippophae rhamnoides L. and Ginkgo, and has multiple pharmacological functions, such as anti-tumor, anti-myocardial hypoxia, and cardiovascular protection. Our previous study has shown that ISO could attenuate lipopolysaccharide (LPS)-induced acute lung injury in mice, but its mechanism is not clear.Methods: In this study, we used LPS-induced mouse and cell models to research the mechanism of ISO alleviating acute lung injury.Results: The results showed that ISO could attenuate the injury of type II alveolar epithelial cells by inhibiting the TLR4/NF-κB pathway. Further studies showed that ISO could inhibit the activation of mTOR signal in vivo and in vitro and promote autophagy in alveolar epithelial cells to reduce lung injury caused by LPS. In addition, ISO could inhibit LPS-induced epithelial cell apoptosis.Conclusion: Overall, ISO could suppress injury and apoptosis of epithelial cells and activate autophagy to protect epithelial cells via inhibiting mTOR signal and attenuating LPS-induced acute lung injury in mice.

Diosmetin has therapeutic efficacy in colitis regulating gut microbiota, inflammation, and oxidative stress via the circ-Sirt1/Sirt1 axis.

Diosmetin (3',5,7 -trihydroxy-4'-methoxy flavone) is a natural flavonoid compound in the citrus species, it exhibits a variety of pharmacological activities, but little is known of its effects on colitis. In this study we evaluated the therapeutic effects of diosmetin on mouse models of chronic and acute colitis. Chronic colitis was induced in mice by drinking water containing 3% dextran sulfate sodium (DSS) from D0 to D8, followed by administration of diosmetin (25, 50 mg · kg-1 · d-1) for another 8 days. Acute colitis was induced by drinking water containing 5% DSS from D0 to D7, the mice concomitantly received diosmetin (25, 50 mg · kg-1 · d-1) from D1 to D7. During the experiments, body weight and disease activity index (DAI) were assessed daily. After the mice were sacrificed, colon tissue and feces samples were collected, and colon length was measured. We showed that in both models, diosmetin administration significantly decreased DAI score and ameliorated microscopic colon tissue damage; increased the expression of tight junction proteins (occludin, claudin-1, and zonula occludens-1), and reduced the secretion of proinflammatory cytokines IL-1ß, IL-6, TNF-α, and Cox-2 in colon tissue. We found that diosmetin administration remarkably inhibited colon oxidative damage by adjusting the levels of intracellular and mitochondrial reactive oxygen species, GSH-Px, SOD, MDA and GSH in colon tissue. The protection of diosmetin against intestinal epithelial barrier damage and oxidative stress were also observed in LPS-treated Caco-2 and IEC-6 cells in vitro. Furthermore, we demonstrated that diosmetin markedly increased the expression of Nrf2 and HO-1 and reduced the ratio of acetylated NF-κB and NF-κB by activating the circ-Sirt1/Sirt1 axis, which inhibited oxidative stress and inflammation in vivo and in vitro. Diosmetin reversed the effects of si-circSirt1 and si-Sirt1 in LPS-treated Caco-2 and IEC-6 cells. When the gut microbiota was analyzed in the mouse model of colitis, we found that diosmetin administration modulated the abundance of Bacteroidetes, Actinobacteria, Cyanobacteria and Firmicutes, which were crucial for inflammatory bowel disease. Our results have linked colitis to the circ-Sirt1/Sirt1 signaling pathway, which is activated by diosmetin. The results imply that diosmetin may be a novel candidate to alleviate DSS-induced colitis and can be a lead compound for future optimization and modification.

Effect of dihydromyricetin on SARS-CoV-2 viral replication and pulmonary inflammation and fibrosis.

BACKGROUND: COVID-19 (Coronavirus Disease-2019) has spread widely around the world and impacted human health for millions. The lack of effective targeted drugs and vaccines forces scientific world to search for new effective antiviral therapeutic drugs. It has reported that flavonoids have potential inhibitory activity on SARS-CoV-2 Mpro and anti-inflammatory properties. Dihydromyricetin, as a flavonol, also has antiviral and anti-inflammatory potential. However, the inhibition of dihydromyricetin on SARS-CoV-2 Mpro and the protective effect of dihydromyricetin on pulmonary inflammation and fibrosis have not been proved and explained. PURPOSE: The coronavirus main protease (Mpro) is essential for SARS-CoV-2 replication and to be recognized as an attractive drug target, we expect to find the inhibitor of Mpro. Novel coronavirus infection can cause severe inflammation and even sequelae of pulmonary fibrosis in critically ill patients. We hope to find a drug that can not only inhibit virus replication but also alleviate inflammation and pulmonary fibrosis in patients. METHODS: FRET-based enzymatic assay was used to evaluate the inhibit activity of dihydromyricetin on SARS-CoV-2 Mpro. Molecular docking was used to identify the binding pose of dihydromyricetin with SARS-CoV-2 Mpro. The protective effects of dihydromyricetin against BLM-induced pulmonary inflammation and fibrosis were investigated in C57BL6 mice. BALF and lung tissue were collected for inflammation cells count, ELISA, masson and HE staining, western blotting and immunohistochemistry to analyze the effects of dihydromyricetin on pulmonary inflammation and fibrosis. MTT, western blotting, reverse transcription-polymerase chain reaction (RT-PCR) and wound healing were used to analyze the effects of dihydromyricetin on lung fibrosis mechanisms in Mlg cells. RESULTS: In this study, we found that dihydromyricetin is a potent inhibitor targeting the SARS-CoV-2 Mpro with a half-maximum inhibitory concentration (IC50) of 1.716 ± 0.419 µM, using molecular docking and the FRET-based enzymatic assay. The binding pose of dihydromyricetin with SARS-CoV-2 Mpro was identified using molecular docking method. In the binding pocket of SARS-CoV-2 Mpro, the dihydrochromone ring of dihydromyricetin interact with the imidazole side chain of His163 through π-π stacking. The 1-oxygen of dihydromyricetin forms a hydrogen bond with the backbone nitrogen of Glu166. The 3-, 7-, 3'- and 4'-hydroxyl of dihydromyricetin interact with Gln189, Leu141, Arg188 and Thr190 through hydrogen bonds. Moreover, our results showed that dihydromyricetin can significantly alleviate BLM-induced pulmonary inflammation by inhibiting the infiltration of inflammation cells and the secretion of inflammation factors in the early process and also ameliorate pulmonary fibrosis by improving pulmonary function and down-regulate the expression of α-SMA and fibronectin in vivo. Our results also showed that dihydromyricetin inhibits the migration and activation of myofibroblasts and extracellular matrix production via transforming growth factor (TGF)-ß1/Smad signaling pathways. CONCLUSION: Dihydromyricetin is an effective inhibitor for SARS-CoV-2 Mpro and it prevents BLM-induced pulmonary inflammation and fibrosis in mice. Dihydromyricetin will be a potential medicine for the treatment of COVID-19 and its sequelae.

Bergenin attenuates bleomycin-induced pulmonary fibrosis in mice via inhibiting TGF-ß1 signaling pathway.

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease characterized by epithelial cell damage, fibroblast activation, and collagen deposition. IPF has high mortality and limited therapies, which urgently needs to develop safe and effective therapeutic drugs. Bergenin, a compound derived from a variety of medicinal plants, has demonstrated multiple pharmacological activities including anti-inflammatory and anti-tumor, also acts as a traditional Chinese medicine to treat chronic bronchitis, but its effect on the pulmonary fibrosis is unknown. In this study, we demonstrated that bergenin could attenuate bleomycin (BLM)-induced pulmonary fibrosis in mice. In vitro studies indicated that bergenin inhibited the transforming growth factor-ß1 (TGF-ß1)-induced fibroblast activation and the extracellular matrix accumulation by inhibiting the TGF-ß1/Smad signaling pathway. Further studies showed that bergenin could induce the autophagy formation of myofibroblasts by suppressing the mammalian target of rapamycin signaling and that bergenin could promote the myofibroblast apoptosis. In vivo experiments revealed that bergenin substantially inhibited the myofibroblast activation and the collagen deposition and promoted the autophagy formation. Overall, our results showed that bergenin attenuated the BLM-induced pulmonary fibrosis in mice by suppressing the myofibroblast activation and promoting the autophagy and the apoptosis of myofibroblasts.

Betulinic acid attenuated bleomycin-induced pulmonary fibrosis by effectively intervening Wnt/ß-catenin signaling.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fatal and progressive fibrotic lung disease lacking a validated and effective therapy. Aberrant activation of the Wnt/ß-catenin signaling cascade plays the key role in the pathogenesis of IPF. Betulinic acid is a natural pentacyclic triterpenoid molecule that has excellent antitumor and antiviral activities. HYPOTHESIS: We hypothesized that BA has an anti-pulmonary fibrosis effect mediated by the suppression of the Wnt/ß-catenin pathway. Study design Pulmonary fibrosis markers were detected in vitro and in vivo to confirm the antifibrotic effect of BA. The Wnt/ß-catenin pathway-related proteins were overexpressed to determine the effect of BA on Wnt signaling. METHODS AND RESULTS: BA dose-dependently inhibited Wnt3a-induced fibroblast activation in vitro. Moreover, BA decreased Wnt3a- and LiCl-induced transcriptional activity, as assessed by the TOPFlash assay in fibroblasts, and repressed the expression of the Wnt target genes cyclin D1, axin 2, and S100A4. Further investigation indicated that BA restrained the nuclear accumulation of ß-catenin, mainly by increasing the phospho-ß-catenin ratio (S33/S37/T41 and S45), inhibited the phosphorylation of DVL2 and LRP, and decreased the levels of Wnt3a and LRP6. In agreement with the results of the in vitro assays, the in vivo experiments indicated that BA significantly decreased bleomycin-induced pulmonary fibrosis in mice and suppressed myofibroblast activation by inhibiting Wnt/ß-catenin signaling. CONCLUSION: BA may directly interfere with the Wnt/ß-catenin pathway to subsequently repress myofibroblast activation and pulmonary fibrosis.

In vitro screening for compounds from Hypericum longistylum with anti-pulmonary fibrosis activity.

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with a poor prognosis and limited therapies, and transforming growth factor-ß1 (TGF-ß1) plays a central role in the pathogenesis of IPF. Here, we aimed to investigate the chemical constituents and biological activities of Hypericum longistylum and detect whether the isolated compounds inhibit the TGF-ß1/Smad3 signaling pathway to identify candidate compounds for the treatment of pulmonary fibrosis. Fifteen compounds (1-15) were isolated from H. longistylum and their structures were elucidated on the basis of spectroscopic analyses. An in vitro MTT assay was used to test the effect of these fifteen compounds on fibroblast cytotoxicity and vitality. Furthermore, their bioactivities were screened using a TGF-ß1/Smad3 pathway luciferase reporter in vitro. MTT screening found that compounds 1-15 had no deleterious effects on normal mouse lung fibroblasts and no significant inhibition of vitality. Luciferase assay showed that compounds 14 and 15 could significantly inhibit the TGF-ß1/Smad3 pathway with the inhibition rates of 67.92% and 93.10%, respectively. Both compounds can be used as lead compounds for structural modification and optimization to obtain more drug candidates for the treatment of pulmonary fibrosis.

Antifibrotic Mechanism of Cinobufagin in Bleomycin-Induced Pulmonary Fibrosis in Mice.

Idiopathic pulmonary fibrosis (IPF) is a progressive and usually fatal lung disease that is characterized by fibroblast proliferation and extracellular matrix remodeling, which result in irreversible distortion of the lung's architecture and the formation of focal fibrous hyperplasia. The molecular mechanism by which pulmonary fibrosis develops is not fully understood, and no satisfactory treatment currently exists. However, many studies consider that aberrant activation of TGF-ß1 frequently promotes epithelial-mesenchymal transition (EMT) and fibroblast activation in pulmonary fibrosis. Cinobufagin (CBG), a traditional Chinese medicine, has been widely used for long-term pain relief, cardiac stimulation, and anti-inflammatory and local anesthetic treatments. However, its role in pulmonary fibrosis has not yet been established. We investigated the hypothesis that cinobufagin plays an inhibitory role on TGF-ß1 signaling using a luciferase-reporter assay. We further explored the effect of cinobufagin on pulmonary fibrosis both in vitro and in vivo. The in vitro experiments showed that cinobufagin suppresses TGF-ß1/Smad3 signaling in a dose-dependent manner, attenuates the activation and differentiation of lung fibroblasts and inhibits EMT induced by TGF-ß1 in alveolar epithelial cells. The in vivo experiments indicated that cinobufagin significantly alleviates bleomycin-induced collagen deposition and improves pulmonary function. Further study showed that cinobufagin could attenuate bleomycin-induced inflammation and inhibit fibroblast activation and the EMT process in vivo. In summary, cinobufagin attenuates bleomycin-induced pulmonary fibrosis in mice via suppressing inflammation, fibroblast activation and epithelial-mesenchymal transition.

Effects of l-arginine on endometrial estrogen receptor α/ß and progesterone receptor expression in nutrient-restricted sheep.

This study aimed to determine the effects of l-arginine (L-Arg) supplementation on steroid hormone receptors in non-pregnant ovine endometrium. All experimental ewes were randomly assigned to either a control group (n = 6), a nutrient-restricted group (n = 6), or an L-Arg supplemented nutrient-restricted group (n = 6). The effects of L-Arg on estrogen receptor α/ß (ERα/ß) and progesterone receptor (PGR) expression in the ovine endometrium were assessed. Our results showed that levels of ERß and PGR expression were significantly increased by nutrient restriction, but L-Arg counteracted the effect of nutrient restriction on ERß and PGR expression (p < 0.05). Also, expression of endometrial ERα was substantially increased (p < 0.05) by L-Arg supplementation. Furthermore, ERα/ß and PGR were mainly detected in the endometrial luminal epithelium and glandular epithelium. Therefore, we isolated and identified endometrial epithelial cells (EECs) from sheep. Different concentrations of L-Arg were added to investigate the effects on ERα/ß and PGR in EECs. The expression levels of endothelial nitric oxide synthase, ERß, and PGR were significantly increased in response to low-concentration (200 µmol) L-Arg supplementation, which subsequently decreased with a high concentration (800 µmol) (p < 0.05). Otherwise, ERα expression was remarkably increased at both L-Arg concentrations in EECs (p < 0.05). Overall, the results indicated that L-Arg performed crucial roles in the regulation of ovine steroid hormone receptor expression in the endometrium. The results of this study provide a theoretical basis and technical means for the normal function of endometrium in response to low nutrient levels.

Synthesis and discovery of a drug candidate for treatment of idiopathic pulmonary fibrosis through inhibition of TGF-ß1 pathway.

In this study, anti-IPF lead compounds 42 and 44, derived from natural sesquiterpene lactones Isoalantolactone and alantolactone, were discovered by screening from a high-throughput TGF-ß1 reporter luciferase assay. Notably, they could reduce the myofibroblast activation and extracellular matrix deposition both in vitro and in vivo. Additionally, compounds 42 and 44 could significantly attenuate bleomycin-induced pulmonary fibrosis in mice. Further validation of pharmacokinetics study and toxicity evaluation indicated that compound 44 might be a promising anti-IPF drug candidate.

Effects of l-arginine on endometrial microvessel density in nutrient-restricted Hu sheep.

Nutrient deficiency in ruminants can lead to estrus cycle disorders, a decreased pregnancy rate, and reduce birth weight. l-arginine (L-Arg), an important amino acid, can improve uterine homeostasis in pregnant sheep and prevent intrauterine growth restriction (IUGR). However, most studies of L-Arg have been conducted on pregnant sheep and few have reported the effects of L-Arg on microvessel density (MVD) in the non-pregnant ovine endometrium. The processes of normal uterine cyclical development and implantation are dependent on a balanced of endometrial MVD. In this study, female Hu sheep were randomly assigned to either a control group (n = 6), a nutrient-restricted group (n = 6), or an L-Arg supplemented nutrient-restricted group (n = 6). The effects of L-Arg on MVD in ovine endometrium were then studied. Our results showed that ovine endometrial MVD was significantly increased by nutrient restriction, but L-Arg counteracted the effect of nutrient restriction on MVD (P < 0.05). Levels of angiogenic growth factors (including VEGFA, VEGFR2, and FGF2) had significant increases (P < 0.05) in endometrium of nutrient restriction on sheep, but that L-Arg supplementation substantially decreased (P < 0.05) their expressions in nutrient restriction sheep. Furthermore, oxidative stress caused by nutrient restriction was also alleviated by L-Arg supplementation in the ovine endometrium. Overall, the results suggested that L-Arg has crucial roles in maintaining the balance of endometrial MVD and angiogenic growth factors, and increasing anti-oxidation capability in the endometrium of nutrient-restricted sheep. This study will provide a theoretical basis and technical means for the normal development of endometrial microvessels in low nutrition level.

Parthenolide attenuated bleomycin-induced pulmonary fibrosis via the NF-κB/Snail signaling pathway.

BACKGROUND: Parthenolide (PTL) is a natural molecule isolated from Tanacetum parthenium that exhibits excellent anti-inflammatory and antitumor activities. Pulmonary fibrosis (PF), especially idiopathic pulmonary fibrosis (IPF), is a chronic lung disease that lacks a proven effective therapy. The present study evaluated the therapeutic effect of PTL on PF. METHODS: Serum-starved primary lung fibroblasts and HFL1 cells were treated with different doses of PTL, and cell viability and the migration rate were measured. Western blot analysis and a dual-luciferase assay were used to analyze the epithelial-mesenchymal transition (EMT)-related transcription factors influenced by PTL treatment in A549 cells and primary lung epithelial cells. Mice with bleomycin (BLM)-induced pulmonary fibrosis were treated with different doses of intragastric PTL, and pathological changes were evaluated using Hematoxylin-eosin (H&E) staining and immunohistochemical analysis. RESULTS: Our results demonstrated that PTL reduced the cell viability and migration rate of lung fibroblasts and inhibited the expression of EMT-related transcription factors in lung epithelial cells. In vivo studies demonstrated that PTL attenuated BLM-induced pulmonary fibrosis and improved the body weight and pathological changes of BLM-treated mice. We further demonstrated that PTL attenuated BLM-induced PF primarily via inhibition of the NF-κB/Snail signaling pathway. CONCLUSION: These findings suggest that PTL inhibits EMT and attenuates BLM-induced PF via the NF-κB/Snail signaling pathway. PTL is a worthwhile candidate compound for pulmonary fibrosis therapy.

[Study on prescription combination and design method based on dichotomy and greedy algorithm].

The prescription combinations of traditional Chinese medicine (TCM) focuses on the taste and channel tropism, the Qi movement, as well as the compatibility according to multiple combination principles and medicinal property and flavor combination of several traditional Chinese medicines. With the in-depth study on the prescription compatibility, researchers have realized that the medicinal property theory is the core of TCM combinations. However, there is no definite method for combinations based on medicinal properties. In this paper, the authors put forward an method for designing prescription combinations based on bipartite graph and the greedy algorithm. With the medicinal property combinations of Siweilurong Pills for example, the authors proved this method could provide ideas for quickly choosing herbal medicines for prescription combinations, and discussed the prospect of this method in substituting previous and endangered herbal medicines and banned medicinal materials.

[Formula method of medicated diet based on medicinal property combination patterns].

To propose a formula method of medicated diet based on medicinal property combination patterns in this paper under the context of lack of innovation in medicated diets. By analyzing the property combination patterns of traditional Chinese medicine and commonly used foods recorded in the pharmacopoeia, medicated diet formulae were optimized by using the greedy algorithm, with the property combination patterns of classical formulae based on the syndrome differentiation and treatment. In this paper, the Baihu Rensheng decoction, which is a classical formula for treating lung and stomach heat-derived diabetes, was taken for example in the formula design. As a result, totally 18 medicated diet formulae were developed and proved to be rational in the analysis on traditional Chinese medicines and nutriology. This method expands the way of thinking for personalized diet therapies and provides theoretical basis the industrial development and clinical application of medicated diets.